Management of patients with chronic disease consumes a significant proportion of the total health care expenditure in the United States. Many of these diseases are widely prevalent and have significant annual incidences as well. Heart failure prevalence alone is estimated at over 5.5 million patients in 2000 with incidence rates of over half a million additional patients annually, resulting in a total health care burden in excess of $20 billion. Heart failure, like many other chronic diseases such as asthma, COPD, chronic pain, and epilepsy, is event driven, where acute de-compensations result in hospitalization.
In addition to causing considerable physical and emotional trauma to the patient and family, hospitalizations consume a majority of the total health care expenditure allocated to the treatment of heart failure. Hospitalization and treatment for an acute de-compensation typically occurs after the de-compensation event has occurred. However, most heart failure patients exhibit prior non-traumatic symptoms, such as steady weight gain, in the weeks or days prior to the de-compensation. If the caregiver is aware of these symptoms, it is possible to intervene before the event, at substantially less cost to the patient and the health care system.
Intervention is usually in the form of a re-titration of the patient's drug cocktail, reinforcement of the patient's compliance with the prescribed drug regimen, or acute changes to the patient's diet and exercise. Such intervention is usually effective in preventing the de-compensation episode and thus avoiding hospitalization. Patients with chronic heart disease can receive implantable cardiac devices such as pacemakers, implantable cardioverter defibrillators (ICDs), and heart failure cardiac resynchronization therapy (CRT) devices. Currently, the electrophysiologist that implants pacemakers and ICDs requires their patients to make clinic visits periodically, usually once every three or four months, in order to verify if their implanted device is working correctly and programmed optimally. Device follow-ups are usually performed by the nurse-staff assisted by the sales representative from the device manufacturers. Device follow-ups are labor intensive and typically require patients to make multiple clinic visits.
The data the caregiver does receive regarding a patient requires the caregiver to analyze the data and provide predictive and post-event diagnosis based on the data. However, as the amount of data collected regarding a particular patient increases, it becomes more difficult for a caregiver to assimilate and provide a meaningful analysis of all of the data. In addition, it is difficult for a caregiver to identify trends and other information from particular patients and leverage this knowledge for the treatment of larger populations.
It would therefore be desirable to develop an automated system to collect data regarding the physiological condition of a patient and to automate the process of analyzing the data.